A McDonald's sign in Arizona toppled off its pedestal Wednesday, severely injuring a Naperville couple who had stopped for lunch, police and relatives said.

Russell and Carolyn Janke were driving back to Naperville after spending the winter in Arizona when they stopped about 12:30 p.m. at a McDonald's in Window Rock, Ariz., said their son, Rick.

Acting Navajo Nation Police Chief Steve Nelson said winds in the area Wednesday "were probably 60 m.p.h.-plus."As the couple sat in their vehicle in the parking lot, the golden arches fell, crushing their Chevy Trailblazer.

The couple were taken to the Indian Health Service in Fort Defiance, Ariz. When the winds died down, Carolyn Janke, 69, was taken to St. Joseph's Hospital and Medical Center in Phoenix.

Russell Janke, 72, suffered a laceration to his head but was alert and able to communicate with authorities, Nelson said. He was in fair condition, his son said. Carolyn Janke was knocked unconscious and suffered a fractured spinal column and sternum, her son said. She was in critical condition, her son said.

Rick Janke said he was "stunned" after learning of the accident about 5 p.m. Wednesday and was trying to catch a flight to Arizona.

Russell, a retired engineer, and Carolyn Janke had raised three children in Naperville. The couple have spent winters in Arizona since the 1990s, their son said.

Nelson said high winds had been gusting across the reservation for the last three weeks, but authorities had not gotten any reports of similar incidents.